No audio when playing some .avi videos

[litianjun05090]

info

libavutil 57. 13.100 / 57. 13.100 libavcodec 59. 15.102 / 59. 15.102 libavformat 59. 10.100 / 59. 10.100 libavdevice 59. 1.100 / 59. 1.100 libavfilter 8. 21.100 / 8. 21.100 libswscale 6. 1.102 / 6. 1.102 libswresample 4. 0.100 / 4. 0.100 Guessed Channel Layout for Input Stream #0.1 : mono Input #0, avi, from '/storage/emulated/0/BaiduNetdisk/我的资源/深入浅出计算机组成原理《更新中》等多个文件/应用软件开发技术(VB.NET)/30.avi': Duration: 00:38:27.00, start: 0.000000, bitrate: 93 kb/s Stream #0:0: Video: mpeg4 (XVID / 0x44495658), yuv420p, 800x600 [SAR 1:1 DAR 4:3], 69 kb/s, 10 fps, 10 tbr, 10 tbn Stream #0:1: Audio: wmav2 (a[1][0][0] / 0x0161), 22050 Hz, mono, fltp, 19 kb/s At least one output file must be specified

Is it because wmav2 not supported ?